PROGRESS-M 21
| Launched | 27 January 1994 |
| Flight ended | 22 March 1994 |
| Status | Decayed |
| Launch site | Tyuratam Missile and Space Center, Kazakhstan (Also known as Baikonur Cosmodrome) |
| Owner | Commonwealth of Independent States (former USSR) |
| NORAD ID | 22975 |
| COSPAR ID | 1994-005A |
| Observing |
Launched alongside
SL-4 R/B